this repo has no description
fix: bump zat to v0.2.2, remove correctness asymmetry caveat
zat now enforces the same size limits as indigo (2MB blocks, 10k max
blocks). there are no remaining correctness differences between the
two decode paths.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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README.md
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README.md
···
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- SHA-256 hash each block and compare against CID digest
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- decode every block as DAG-CBOR
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**what both do that isn't obvious:**
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- enforce size limits (2MB max on blocks field, max block count) — zat matches indigo's limits as of v0.2.2
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**what neither side does:**
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- DAG-CBOR deterministic encoding validation (sorted keys, minimal integers) — indigo's refmt doesn't check this either
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- signature verification — separate from decode, not measured here
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- MST validation — separate from decode, not measured here
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**the only asymmetry:** indigo enforces size limits on CBOR map lengths and a 2MB cap on the blocks field. these are integer comparisons — effectively free.
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the ~20x gap between zat and indigo (both with CID verification) is entirely implementation cost, not correctness differences.
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there are no correctness differences between the two decode paths. the ~20x gap is entirely implementation cost.
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## where the ~20x comes from
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···
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| lang | SDK | version | CBOR engine | CAR engine |
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|------|-----|---------|-------------|------------|
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| zig | [zat](https://tangled.sh/@zzstoatzz.io/zat) | 0.2.1 | hand-rolled | hand-rolled (+ SHA-256 CID verify) |
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| zig | [zat](https://tangled.sh/@zzstoatzz.io/zat) | 0.2.2 | hand-rolled | hand-rolled (+ SHA-256 CID verify, size limits) |
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| rust | raw (minicbor + bumpalo) | — | [minicbor](https://crates.io/crates/minicbor) (zero-copy) | hand-rolled (sync) |
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| rust | [jacquard](https://github.com/rsform/jacquard) | 0.9 | [ciborium](https://crates.io/crates/ciborium) (header) + [serde_ipld_dagcbor](https://crates.io/crates/serde_ipld_dagcbor) (body) | [iroh-car](https://crates.io/crates/iroh-car) (async) |
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| go | raw (fxamacker/cbor) | — | [fxamacker/cbor](https://github.com/fxamacker/cbor) | hand-rolled (sync, no CID verify) |
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zig/build.zig.zon
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zig/build.zig.zon
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.minimum_zig_version = "0.15.0",
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.dependencies = .{
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.zat = .{
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.url = "https://tangled.sh/zat.dev/zat/archive/v0.2.1",
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.hash = "zat-0.2.0-5PuC7igtBAC6Pl01Kyqn0c-1iBFuwYAlxj9Nvf3515Su",
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.url = "https://tangled.sh/zat.dev/zat/archive/v0.2.2",
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.hash = "zat-0.2.0-5PuC7mAuBADmN7OZkGvymjk9jq4akxdl-IlHSo8r25pr",
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},
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},
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.paths = .{